Currently, it is not financially viable, or is only feasible with difficulty, to remove the deposited varnish layer(s) of dip-coated substrate before firing. Defectively coated substrates are generally disposed of or have to be reworked in costly processes. The document DE 10 2013 201 966 A1 discloses a novel method for coating metallic surfaces and the coating systems used for this purpose, by which a dispersion of film-forming polymers and an anionic polyelectrolyte in the form of an ionogenic gel is deposited by cations dissolved out of the metallic surface. The entire content of the aforementioned document should form part of the present application. The coating systems described therein are designated, in the context of this application, as universal dip coats.